Australia has dispatched 50 federal police officers to London who are on standby to secure the Malaysia Airlines Flight MH17 crash site, Prime Minister Tony Abbott has said, as teams prepared to fly the bodies of more victims to the Netherlands.

Mr Abbott, who says he fears some remains will never be recovered unless security is tightened, has proposed a multinational force spearheaded by countries such as Australia, the Netherlands and Malaysia that lost citizens in the disaster.

"We are ready to deploy Australian police to the Ukraine, to help secure the site as a part of an international team under United Nations authorities," he told a press conference in Cranberra.

His announcement came as more bodies from the crash site, where 298 passengers died, were loaded onto military aircrafts in Kharkiv airport headed for the Netherlands to be identified. At least 200 bodies were aboard the train that brought them from the crash site to Kharkiv earlier this week.

Mr Abbott said he has spoken with Ukrainian President Petro Poroshenko and Russian President Vladimir Putin about ensuring safe access for the officers, who would be tasked with securing the crash site for investigators.

But making the situation more difficult is the armed men controlling it who have "a vested interest in the result of the investigation".

"We want to deploy them as quickly as possible because right now there could well be remains exposed to the European summer, exposed to the ravages of heat and animals," said Mr Abbott.

Video: Experts examining the crash

"On the site, it is still clear that nothing is happening without the approval of the armed rebels, who most likely brought the plane down in the first place," he added.

Mr Abbott said Operation Bring Them Home, first announced on Tuesday, was underway to repatriate the bodies of 37 Australian victims of the 17 July crash.

The move comes after Mr Abbott claimed on Tuesday Russian-backed rebels who control the area were tampering with evidence on "an industrial scale" and argued outside police or possibly military force was needed to ensure that did not continue.